Are Clam Shells Compostable?

For those who are religious and subscribe to Christianity, the Bible’s book of Genesis describes God’s creation of the world. In chapter 1 verse 20, God said “Let there be water teem with living creatures…” And just like that, we understand where all the sea fish come from.

Some of the seafood we know and love to eat include fish, lobsters, and shellfish. As the name suggests, shellfish are characterized by an inedible shell which is usually thrown away when having your food.

The shells in clams may however be of more importance and should rather be composted or used as fertilizer than thrown away. This article has more on clamshells.

Can You Compost Clam Shells?

Of course, you can compost clamshells. They actually benefit your compost bins in more ways than you think. The shells can balance out the acidity which helps normalize the pH levels in your compost bin. If you happen to love seafood or live in an area with lots of seafood, then you are in luck.

Adding clamshells will greatly improve your compost and subsequently your garden and crops. However, you should not add the shells whole as they are or while filled with meaty flesh.

Instead, you should clean them first by removing or scraping any leftover meats and then rinsing them with running water. Cleaning them also takes out the excess salt, sauces and heavy oils that might be present on the shells.

If the meat is left there and sent to the compost, it will invite pests to the fold, who will do all they can to disrupt your hard work. The oils and sauces may halt the entire process as well by affecting the bacterial working on your compost.

Next, you will want to crush the shells until they are almost gravel-like. Crushing the shells removes no nutritional properties from the shells, but ensures all parts of the shells decompose quite easily and quickly.

If composted whole, the shells will take quite a long time before breaking down fully. You will then add the gravel-like shells at the top of nitrogen-rich materials.

You will then bury them all with more layers of your already-existing pile, or if it is fresh compost, mix the materials with carbon-rich materials. Clamshells will do wonders for the compost pile as they will balance out the acidity of a compost pile, restoring the overall pH of the final compost to almost neutral.

Such a compost will work best with all sorts of soils and crops, although some plants may require a slightly acidic compost with others preferring a slightly alkaline one.

Balancing out the acidity inside the composting bin is also vital as acidic compost may slow down the entire process. A slow compost will mean you wait longer for the final compost, which is really not what you or your garden want.

Also, when composting clamshells, it might work best if you bury them at the center of the composting pile. That is where it is hottest and placing the shells there will ensure they decompose quite quickly.

The center of the pile will also hide the stinky smells that come from composting organic matter, which while unwelcome to the human nose, are very welcoming to nosy pests.

The same process of composting clamshells also applies to composting lobster, crab, oyster and mussel shells. Simply clean and then crush them before adding them to the center of the composting pile.

Are Clam Shells Good For the Garden?

Oh yes, clamshells are good for the garden. Clamshells are also a rich source of calcium and important plant micronutrients. They, therefore, make for a valuable addition and sustainable amendment to the compost and the home garden.

The hard clamshells are composed mainly of calcium carbonate and chitin. Calcium carbonate, a compound also present in eggshells, adds much-needed calcium to the soil.

The calcium that is contained within the crushed shells enters the soil after each shell breaks down. Their calcium content also helps to balance soil pH levels, improves nitrate uptake, aids enzyme formation and strengthens plant cell walls. You can also use clamshells to keep garden pests away.

Chitin, on the other hand, is an organic polymer that forms the backbone of the shells of shellfish and insects and has nitrogen in its molecular structure. Therefore, as the shells break down, they will also add nitrogen to the soil.

Ground shells can be either composted or added directly to the soil as fertilizer. The marine materials naturally release nutrients into the soil and help maintain a healthy pH and nutrient balance that can greatly benefit your plants.

Crushed clamshells work greatly for various outdoor projects because they are both environmentally friendly and provide high-quality drainage. Therefore, whether you compost clamshells or use them as fertilizer directly, they are a great addition to the soil and plants.

What is more, they are a readily available and environmentally-friendly fertilizer that eliminates the need for or overreliance on poisonous chemical fertilizers

How Long Does It Take For Clam Shells to Compost?

The duration upon which clam shells decompose is entirely dependent on the state they were in at the time they were being introduced to the composting bin. If they were crushed and ground before being added to the composting process, they will fully decompose in a matter of weeks or very few months.

If they were not crushed, they can take years before they even begin to decompose. If the shells were buried in sediment like on the floor of the sea, they will dissolve more slowly.

Also, shells have been known to decompose a bit faster in a wet environment. This, therefore, means that if you do not aerate and moisturize your compost, the duration takes a longer duration.

Therefore, ensure your compost is going on well and does not stall. Eliminate any ingredients that could halt stall the process like excessively greasy substances or pesky pests that could interrupt the process.

Can Clam Shells Decompose?

Of course, clamshells can decompose. The majority of naturally occurring matter, also known as organic matter, is biodegradable and can therefore decompose. Clamshells, fall into this category and have been known to decompose, explaining why they are compostable.

The rate of decomposition depends on several factors, but they all end up decomposing. If the shells are crushed into smaller pieces, they take weeks or months to fully decompose while if they were left alone as they were whole, they can take years to do so.

When breaking down, the shells release mineral materials to the ground, and that is why the majority opt to compost them so that they can harness the power of such minerals, including calcium, and apply them to their gardens.

Clamshells, like bones and other seashells, decompose much slowly, especially if left whole. The good thing is that over time, they release the minerals they have into the soil, especially calcium.

This can happen rapidly when the shells are left to lie on the ground surface, or even on the bottom of the sea. If you mix the clamshells into the soil, the coarseness will improve the drainage of said soil, positively benefiting any plant that likes well-drained soil.

Therefore, as a home gardener, do not throw away your seashells, but rather use them as mulch, fertilizer or add them to your compost. They will do more good to your garden in the long run, since they are biodegradable. What’s more, they are an organic addition to the soil, making you a better environmentalist.

What Can You Do With Leftover Clam Shells?

1. Make clam shell broth

Seafood broth has always been far less popular than chicken, beef and veggie stock, which in my book should be criminal. Seafood broth is delightful and is easy to make.

It also shows how resourceful you are. You only need to take your clamshells, add some aromatics, herbs and water, and simmer for a few hours.

Clam, mussel and oyster shell broth does not have the tastier flavor of shrimp, crab or lobster shell broth, but it will still do the trick. Your perfect clamshell stock or broth will be ideal for risottos and soups.

2. Use them as a soap dish

The larger clamshells can be used to hold soap in your bathroom, kitchen and shower sinks. They can be found in abundance and repurposed to fit this description. A larger clamshell will work perfectly for a standard size bar of soap, although other seafood shells are bigger, or could play a similar role.

3. Hold your salt

Seafood and salt go hand in hand; you cannot think of one without the other. It is therefore perfect that leftover shells can act as salt bowls.

Some seashells can play the role better than clamshells, like oysters, but clamshells will still do the trick. Do not throw your leftover shells away, but instead, repurpose them as salt bowls or dishes.

4. As a jewellery holder

The fun thing about repurposing shells is that they are not always immediately recognizable. You can use your clamshells to hold your or your partner’s earrings and rings.

When you perfectly work on the clamshells and use them to hold your jewelry, you will surely be hailed by your friends and colleagues as creative. They are really cute and will do the trick just fine.

5. Presenting your food

This could be an old-fashioned way of thinking but honestly, it still looks great. It is not unusual to find some hotels presenting some foods in clamshells and would not be any different if you did the same to your visitors.

Small clamshells work well for appetizers while other seafood shells carry much more food. Imagine slurping broth from a clamshell, or better yet, slurping clam shell broth from a clamshell. Who said you cannot have your cake and eat it too?

6. Mulch using clamshells

This might be a little like the findings captured above. However, here we go: you can still choose your shells as the ideal mulch. Mulching is the single most important thing you can do to maintain your garden beds.

It helps hold the moisture in the soil, keeps root temperature eve, and also controls weeds by either blocking or smothering out the weed seeds. When you crush your shells and use them as mulch, they will be performing these tasks as well as adding calcium to the plants, aiding in their growth.

Unlike other materials that can be used as mulch, the shells will not decompose shortly after and could take months before they also become part of the soil.

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About Rinkesh

A true environmentalist by heart ❤️. Founded Conserve Energy Future with the sole motto of providing helpful information related to our rapidly depleting environment. Unless you strongly believe in Elon Musk‘s idea of making Mars as another habitable planet, do remember that there really is no 'Planet B' in this whole universe.